: The University of Maryland STAR TRACK Adolescent HIV Program (STAR TRACK Program) is a clinical and research unit with significant experience in the areas of adolescent HIV research. STAR TRACK is the only adolescent exclusive HIV service in the state of Maryland and has a comprehensive "one stop shopping" model of care, a state wide community outreach program, an HIV early identification program through an adolescent specific HIV counseling and testing unit, and a Youth Care Network that serves as referral network for both HIV+ and HIV-youths. Our program has been one of 15 sites of the Adolescent HIV/AIDS Research Network since 1994 with a successful track record of recruitment, retention, site performance, quality assurance. Our PI, study coordinators, and Youth Community Advisory Board member have productively participated in and contributed towards the AMHARN mission and its goals. Our program has extensive experience in the recruitment and retention of HIV+ and HIV-adolescents in clinical care and research, and an active caseload of 105 HIV+ youths (many of whom have research experience) and 125 HIV-youths. STAR TRACK has strong clinical and research collaborations with other clinical sites for a total of 180 HIV infected young people under the age of 24. Our program has highly experienced adolescent researchers and study coordinators as well as basic and clinical researchers of the Division of Pediatric Immunology and the Institute of Human Virology of the University of Maryland. These investigators have an extensive track record of leadership in multicenter collaborative trials. The tight interface between community outreach, early identification of HIV, linkage to care and research, and comprehensive primary and subspecialty care, intrinsic to STAR TRACK?s structure, facilitates the major goals of the ATN. These relationships also provide a great structure to expand subject recruitment. This application details the current clinical and research capacity of the Adolescent Medicine Trial Unit (AMTU) to conduct research protocols related to the primary, secondary and tertiary prevention of HIV. High-risk populations available for this research include high-risk sexual minority and heterosexual youths, as well as incarcerated and substance abusing youths. In addition, it includes youths in transitional housing situation and school dropouts. Furthermore, the strong collaboration with an experienced laboratory, database manager and other University of Maryland scientists with expertise in HIV clinical trials and vaccine development provides an optimal environment for enriching the basic science and laboratory-based agenda of the ATN.